Glossary

Arch

Types include: Basket arch or Anse de Panier (French, lit. basket handle): three-centred and depressed, or with a flat centre. Chancel: dividing chancel from nave or crossing in a church. Crossing: spanning piers at a crossing in a church. Depressed or three-centred: with a rounded top, but curving inward more at the sides. Four-centred: with four arcs, the lower two curving inward more than the upper, with a blunt central point; typical of late medieval English architecture. Jack arch: shallow segmental vault springing from beams, used for fireproof floors, bridge decks, etc. Ogee (adjective ogival): a pointed arch with a double reverse curve, especially popular in the 14th century; a nodding ogee curves forward from the wall face at the top. Parabolic: shaped like a chain suspended from two level points, but inverted. Relieving or discharging: incorporated in a wall to relieve superimposed weight. Shouldered: with arcs in each corner and a flat centre or lintel. Skew: spanning responds not diametrically opposed. Stilted: with a vertical section above the impost i.e. the horizontal moulding at the springing. Strainer: inserted in an opening to resist inward pressure. Three-centred: see Depressed, above. Transverse: spanning a main axis (e.g. of a vaulted space). Triumphal arch: influential type of Imperial Roman monument, free-standing, with a square attic or top section and broad sections to either side of the main opening, often with lesser openings or columns. Tudor: with arcs in each corner joining straight lines to the central point. Two-centred: the simplest kind of pointed arch.

Bay

Division of an elevation or interior space as defined by regular vertical features such as arches, columns, windows etc.

Rib-vault

A vault with a masonry framework of intersecting arches (ribs) supporting cells, used in Gothic and late Norman architecture. A wall rib or wall arch spans between wall and cell vault. A transverse rib spans between two walls to divide a vault into bays. In a quadripartite rib-vault, each bay has two pairs of diagonal ribs dividing the vault into four triangular cells. A sexpartite rib-vault, usually set over paired bays, has an extra pair of ribs springing from between the bays. More elaborate vaults may include ridge-ribs along the crown of a vault or bisecting the bays; tiercerons, extra decorative ribs springing from the corners of a bay; and liernes, short decorative ribs in the crown of a vault, not linked to any springing point. A stellar or star-vault has liernes in star formation. A fan-vault is a form of vault used after c. 1350, made up of halved concave masonry cones decorated with blind tracery.

Vault

An arched stone roof, sometimes imitated in timber, plaster etc. For the different kinds see barrel vault, fan-vault, groin-vault, rib-vault, sail vault.